Early signs of brain changes associated with dementia can be linked to two personality traits - neuroticism and conscientiousness, according to a new study published in the journal Biological Psychiatry.

Researchers combined data from the Baltimore Longitudinal Study of Aging (BLSA) and a meta-analysis of 12 studies on personality and Alzheimers neuropathology published earlier. Taken together, more than 3000 participants were involved. None of the participants had dementia or any other medical condition at the time of study entry in the BLSA neuroimaging sub-study. The five-factor personality test was used to assess personality. The BLSA participants underwent amyloid (11C-labeled Pittsburgh Compound B) and tau (18F-flortaucipir) PET scan.

Researchers evaluated two personality traits (neuroticism and conscientiousness). Neuroticism measures the individual’s propensity for negative emotions, while conscientiousness is the trait of being careful, organized and responsible.

Neuroticism was associated with higher (OR = 1.68) and conscientiousness with lower (OR = 0.61) cortical amyloid deposition in the cognitively normal participants from the BLSA trial. A similar association was noted for deposition of tau in the entorhinal cortex.

The meta-analysis of 12 studies found more amyloid deposition in persons with higher neuroticism and lower conscientiousness. Likewise, persons with higher neuroticism and lower conscientiousness also showed greater deposition of tau in the meta-analysis of 8 studies.

In both the BLSA and meta-analysis, persons who scored higher in neuroticism and lower in conscientiousness had higher deposition of amyloid and tau demonstrating an association of personality traits with neuropathology of dementia. The study further suggests that it may be possible to predict the build up of amyloid and tau, which act as drivers of the neurodegenerative process, and identify such individuals even before dementia manifests clinically and symptoms become evident. Developing a more adaptable personality can ward off such pathological changes.

Reference

1. Terracciano A, et al. Personality associations with amyloid and tau: Results from the Baltimore Longitudinal Study of Aging and meta-analysis. Biological Psychiatry, 2021; DOI: https://doi.org/10.1016/j.biopsych.2021.08.021.